A workpiece spindle is understood in this case to be any spindle-shaped element that can receive a workpiece, either directly or via a further mounting. If appropriate, a carrying basket for small parts can also be fastened to a workpiece spindle, which small parts, for their part, are placed loosely in this carrying basket. Such a workpiece spindle is normally approximately one meter long, but may also be only a few centimeters long, depending on the type of workpieces to be conveyed.
Spindle conveyors, of the type stated at the outset, that are known from the market are used, in particular, to convey vehicle wheels through successive treatment stations of a coating installation, in which the vehicle wheels are provided with a surface coating in a plurality of treatment steps. In such cases, the workpiece spindles are aligned vertically.
In the treatment stations, the workpiece spindles of the transport carriages also become wetted with coating materials, for which reason these transport carriages have to be cleaned from time to time.
For this purpose, in the case of spindle conveyors known from the market, and plants of the type stated at the outset, the transport carriages are routed through a cleaning station, in which the workpiece spindles are sprayed with a cleaning solution, from the side. Cleaning solution loaded with coating material may then drip down on to the running gear of the transport carriages that is located underneath, or on to the rail system, resulting in after-soiling. This, in turn, increases the amount of servicing and cleaning work, since this soiling, likewise, must be removed.
Alternatively, soiled workpiece spindles are detached from the transport carriages and exchanged for cleaned workpiece spindles.
It is therefore an object of the invention to create a spindle conveyor and a plant of the type stated at the outset, in which there is a reduced risk of after-soiling of the components, in particular in the cleaning operation, in particular if the workpiece spindles remain on the transport carriage during cleaning.